UNITED STATES PATENT OFFICE. LEWIS CROOKE, OF NEW YORK, N. Y. IMPROVEMENT IN TN PATED SHOT.

Specification forming part of Letters Patent No. 204,29s, dated May 28, 1878; application filed March 9, 1878. To all whom it may 0.20e, tern of the shot-tower, before they have had city,Be county, it known and that State I, LEWISCROOKE, of New York, of have the eithertime tosimultaneously become oxidized, or consecutively, and are treated, with made an invention of a new manufacture of an acid solution of a salt of tin, and with agi burnished tin-plated projectiles, and an im tation sufficient to burnish then. The said so provement in the art of manufacturing pro lution of tin, which I have used with the best jectiles; and that the following is a full, clear, success, is made of the following ingredients and exact description and specification of my and in the following proportions, the quantity said invention. made at any one time being varied as found Shot and balls for fire-arms to be used by expedient: One pound of crystallized proto hand are made of lead or some of its alloys, chloride of tin is dissolved in eight gallons of and are generally blacked and polished by water, and three-quarters of a pound of com means of black lead or graphite. Such shot mercial nitric acid is added to the solution. are objectionable for several reasons. In the The shot to be treated are charged-into a first place, the process of blacking and polish tumbling-barrel, or other mechanical agitator ing the shot by means of graphite produces a lined with glass or other material having a dust which is highly injurious to the work smooth vitrified surface, and a sufficient quan men employed to do the manual labor. . The tity of the compound acid solution is added to shot also are disagreeable to handle, and pro fill the interstices between the shot and just duce the rapid fouling of shot-guns. They cover them. The tumbling-barrel is then are affected by contact with the flesh or juices closed, and is agitated briskly until metallic of the game shot with them, so that salts of tin is deposited from the solution upon the lead are speedily produced, which are injurious shot in the form of a plating or thin coat there to those who eat the game. of The rapid agitation of the shot in the The subject of the present patent is a new glass-surfaced barrel causes the consolidation manufacture of shot and balls which is free of the deposited tin-plating, and also its bur from the above-stated objections, and also an Inishing, so that when the work is done the improvement in the art of manufacturing shot shot produced have bodies of lead, or an alloy and balls. s thereof, coated with a highly-burnished plat The new manufacture consists of burnished ing of tin. tin-plated shot and balls, or, in other words, The kind of tumbling-barrel which I prefer of shot and balls which are both tin-plated to use is one having trunnions transverse of and burnished, so as to present a bright me its length, whereby a brisk agitation can be tallic surface that does not soil the hands or readily effected. The time required for the the gun, and does not produce poisonous com agitation is generally about five minutes, but pounds. may be prolonged, if deemed expedient. The improvement in the art consists of the If deemed expedient, the process may be va treatment of projectiles composed in part or ried by first treating the shot or balls with the wholly of lead with a solution of a salt of tin, tin solution, hot or cold, in any ordinary wooden and with agitation, either separately or con tumbling-barrel, or by first treating them with jointly, the effect of the first-named treatment the tin solution by simply steeping them with being the plating of the shot with tin, and the out agitation in a quantity of the tin solution effect of the second-named treatment being sufficient to cover them, and, after the shot the burnishing of the plated shot. have been plated with tin, by charging them In order that the invention may be fully un with water into a glass-lined tumbling-barrel, derstood, I will proceed to describe the best in which they are agitated until their surfaces mode which I have thus far devised of pro become burnished. ducing the said new manufacture. Shot which have previously been polished When tin-plated shot are to be made the by the use of graphite may be used for my lead shot are taken in the damp condition in new manufacture, provided they be first which they exist when removed from the cis cleansed of the graphite and lead oxide and 2 20429S of any grease which may adhere to them. Other tin-plating solutions may be used, Shot, also, which have laid in stock after be either hot or cold, as found expedient. ing taken from the cistern of the shot tower Lead shot previously cleansed of lead oxide may be used; but in such case, as their sur may be electroplated with tin by treating them faces are generally oxidized, it is expedient to simultaneously with a proper solution of tin cleanse them by agitation with a Weak solu and a current of electricity obtained from a tion of nitric acid before subjecting them to galvanic battery, or by other means. A proper the tin solution. solution for this purpose may be made by dis If burnished tin-plated lead balls are to be solving in two gallons of water half a pound produced, they may be made by the use of the of pyrophosphate of soda, and by adding to same solution and agitation as above de the solution one pound of crystallized proto scribed for shot. chloride of tin. This solution may be weak In operating with the acid tin solution above ened by the addition of water, if deemed ex described by me, care should be taken that the pedient. solution is not milky in appearance, nor does This same solution may be used in connec not become so when applied to the shot or tion with metallic zinc, without a battery. In balls. If the solution be milky when made, it this case the shot to be treated are charged is an evidence that more nitric acid should be into an ordinary tumbling-barrel, with a suf. added to it, andlifit becomes milky whenincon ficient quantity of solution to cover them, and tact with the shot it is an evidence that more with a quantity of granulated zinc, which need of the solution should be used, as well as more not exceed one-tenth of the weight of the shot. nitric acid. The solution most expedientforany The shot are then agitated in the tumbling particularlot of shot may readily be found by barrel until the plating is effected-say, for a commencing the treatment with the compound period of ten minutes. Or, in place of charg solution described, and then varying its com ing zinc into the tumbling-barrel, the latter position as circumstances or the peculiar na may be formed of zinc, or may be lined with ture of the lead shot show to be expedient. that material. The invention of my new manufacture is After the shot have been tin-plated by the not restricted to the means above described above treatment they may be burnished by of producing the same, because the shot may agitating them in an ordinary tumbling-barrel be plated with tin otherwise, and may then with sawdust, or, better, by agitating them in have their tin-plated surfaces burnished by a glass-lined tumbling-barrel with water. agitation in a glass tumbling-barrel, or one My new manufacture is not restricted to pro faced or lined with glass or its equivalent. jectiles having bodies of pure lead, as either On the other hand, the process or improve lead or its alloys may be employed for such ment in the art above described by me is not bodies. On the other hand, the invention set restricted to the peculiar acid solution of tin forth and claimed in this patent does not in above described, as other solutions of tin may clude the manufacture of projectiles of lead be used with success. Thus, for example, a coated with tin which is not burnished or pol solution of tin for plating may be prepared by ished; nor does it include the process of plat dissolving one pound of protochloride of tin ing lead articles with tin without agitating and two pounds of chloride of sodium in eight them. gallons of water, to which half a pound of hy I claim as my invention drochloric acid (commercial) has been added; 1. Burnished tin-plated projectiles having a and, if deemed best, the action of the solution body of lead coated with burnished metallic may be aided by heat, applied by introducing tin, substantially as before set forth, the same steam into the tumbling-barrel by means of a being a new article of manufacture. pipe inserted through one of the trunnions 2. The improvement in the art of manufac thereof. turing projectiles, consisting, substantially as Another solution which produces good re before set forth, of the treatment of projec, sults is obtained by dissolving one pound of tiles with a solution of tin, and with agitation crystallized protochloride of tin in one quart whereby said projectiles are not only tin-plated, of water containing two ounces of hydro E. have bright metallic surfaces imparted to chloric acid, (commercial,) and by then adding them. to the solution so produced four gallons of a Witness my hand this 7th day of March, A. solution of bitaritrate of potash acidulated D. 1878. with four and a half ounces of nitric acid, LEWIS CROOKE. (commercial.) The solution of the bitartrate Witnesses: may contain about half a pound of the bitar C.T. BRUEN, trate for the four gallons of water. JOHN M. BARRINGTON.